Nowadays, the petroleum extraction gives the formation of water in crude oil emulsions, crude oil in water or inclusive ternary emulsion as water/crude oil/water and crude/water/crude These kinds of emulsion are produced by the turbulence provoked through pumping potency employed in the petroleum wells. The emulsions are favored and stabilized by natural compounds in the crude oil such as clays, naphthenic acids, oxidized hydrocarbons and asphaltenes. Emulsified water has dissolved salts such as calcium and magnesium carbonates, chlorides and sulphates and iron oxides and silica. If the emulsified water is not separate of crude oil, corrosion and scaling in all subsequent refining process (pipeline, storage tanks, distillation columns, heat exchangers, catalysts, piping system, etc.) can occur causing damage to the equipment. Additionally, produced crude oil should comply with international quality norms regarding water and salts maximum quantities, for its possible exportation [1].
Taking into account the previously described, it is convenient from economical point of view to separate water of the emulsion and simultaneously reduce the salt content in the crude oil.
At the beginning of last century, different chemical products have been used to break up water-crude oil emulsions, commonly those are added with constituted composition for emulsion breaking agents, coalescent agents and clarifiers. Most of these products are polymers, for example:
Alkoxylate alkylphenol-formaldehyde resins [2], alkoxylated epoxy resins [2], polyoxyethylene-polyoxypropylene-polyoxyethylene (POE-POP-POE) block copolymer and polyoxypropylene-polyoxyethylene-polyoxypropylene (POP-POE-POP) employing different initiators such as ethylendiamine or propylenglycol [3], polyethers, polyesters and polyurethane polyesters link by carboxylic diacids and diisocyanates [4], aliphatic and aromatic anhydrides in combination with esterified glycolic resins [5], crosslinking ethylcellulose over nano magnetic particles in combination with the application of extern magnetic fields [6], cationic surfactants [7], symmetric surfactants with space fragments like polyoxyethylene [8] between some others.
The Petroleum Mexican Institute (Molecular Engineering Program) has proposed several solutions to the dehydrated and desalted problem of crude oils. So far, the research group has presented five patent applications in the specific area of the applied scientific research. Two describe the utilization of formulation of triblock copolymer of ethylene polyoxide-propylene polyoxide-ethylene polyoxide and that are bifunctionalized with amines, for dehydrating heavy crude oil, achieving water removal around of 30 until 80% and salts of heavy crude oil around of 30 until 65% [9-10]. Another patent application discloses the application of ionic liquids individually and in formulation for dehydrating and desalting medium, heavy and superheavy crude oils (API gravity between 8 and 20) where efficiencies of dehydrated and desalted reached around 90% and 76%, 90% and 71%, 90% and 71%, respectively, and where the addition of the additive was in concentrations between 50 and 2000 ppm [11]. In another patent application, the synergic application of formulations of liquid ionic (LI's) and formulations of triblock copolymer α,ω-bifunctionalized with amines of type ethylene polyoxide-propylene polyoxide-ethylene polyoxide, each one of them individually or in formulations, in crude oils with gravities between 90 and 30° API [12]. Applicants copending application discloses the synthesis of novel triblock copolymers α,ω-bifunctionalized with tertiary amines (aliphatic and aromatics) and the application individually and in formulation as dehydrating and desalting agents of heavy crude oils whose gravities API are between 14-23° API [13].